With an estimated 400 known cases in the U.S.1, Lambert-Eaton Myasthenic Syndrome (LEMS) is a rare, autoimmune, neurological disorder in which the body's immune system attacks its own tissues. With LEMS, the body specifically attacks the neuromuscular junction—i.e. the connections between nerves and muscles. This causes weakness in the upper legs, hips, upper arms, and shoulders. Both walking and self-care can be difficult.
More than 50% of LEMS cases happen in middle aged or older people, with symptoms often occurring prior to the diagnosis of lung cancer.2 Because cancer cells share some of the same proteins as nerve endings, it’s thought that the body attacks nerve endings in an attempt to kill cancer cells. In the other half of LEMS cases, the cause is unknown and typically occurs around age 35.
Signs and Symptoms
LEMS is characterized by weakness starting in the legs and hips, progressing to the arms and shoulders. Onset of signs and symptoms is typically gradual. Additional signs and symptoms may include:
Muscle aches
Muscle weakness that gets worse with time
Fatigue
Difficulty walking and climbing stairs
Difficulty lifting objects and raising arms
Drooping eyelids
Dry eyes
Dry mouth
Blurred vision
Difficulty swallowing
Dizziness upon standing
Constipation
Erectile dysfunction
It’s important to note that because of similar symptoms of muscle weakness, LEMS is often misdiagnosed as Myasthenia gravis (MG). However key differences are in the severity and type of muscle weakness. For example, eye weakness tends to be milder in LEMS patients and unlike MG, is typically not the only symptom. Severe respiratory muscle weakness found in MG is also rare for people with LEMS.
Treatment Options
Although there is no cure for LEMS, treatment can help relieve and lessen symptoms. If LEMS is connected to a cancer diagnosis, treatment is first targeted at the cancer which may then greatly improve LEMS symptoms.
Medicines to help nerve signals reach the muscles as well as immunosuppressants (like steroids) can help relieve symptoms. If symptoms are advancing and other treatments have not helped, both plasmapheresis (plasma exchange) and intravenous immunoglobulin (IVIG) are used to treat LEMS.
Plasmapheresis redirects blood through a machine which filters out the antibodies attacking the nerves. IVIG, which is immunoglobulin given intravenously or through a vein, suppresses the inflammatory response. Derived from thousands of healthy blood plasma donations, immunoglobulin therapy can help suppress an overactive immune system by preventing it from attacking healthy cells.
Helpful Resources
The Muscular Dystrophy Association provides support, education, care, and advocacy for patients with neuromuscular diseases, like LEMS, and their families and/or caretakers. Some of these resources include:
Community resources like access to transportation, clinical trials finder tool, and equipment assistance
How BioMatrix Can Help
Though an LEMS diagnosis can feel overwhelming for you or a loved one, it’s important to know that you are not alone. Organizations like the Muscular Dystrophy Association mentioned above can provide a wealth of information and support as well as connect you to others in the community who have experienced the same diagnosis as well as others with neuromuscular conditions. In addition, your specialty pharmacy can offer individualized support to help manage treatment.
BioMatrix helps manage the individual needs of patients requiring IVIG therapy. Knowledgeable pharmacists and care coordination staff guide each patient through the potential medication side effects and, working with the prescribing physician, help manage treatment to reduce the prevalence and severity of symptoms.
The BioMatrix clinical team includes compassionate nurses who have extensive training and experience with rare diseases, infusion therapies, and complex medical conditions. Our nurses work together with patients, caregivers, pharmacists, and prescribers to coordinate the optimal site of care, conduct nursing interventions, and provide patient education.
Learn more about how our individualized specialty pharmacy services for patients with LEMS and other neurological and neuromuscular conditions.
DISCLAIMER: THIS IS NOT MEDICAL ADVICE. All information, content, and material is for informational purposes only and is not intended to serve as a substitute for the consultation, diagnosis, and/or medical treatment of a qualified physician or healthcare provider. Please consult a physician or other health care professional for your specific health care and/or medical needs or concerns and never disregard professional medical advice or delay in seeking it because of something you have read here or on our website.
Stay informed on the latest trends in healthcare and specialty pharmacy.
Sign up for our monthly e-newsletter, BioMatrix Abstract.
By giving us your contact information and signing up to receive this content, you'll also be receiving marketing materials by email. You can unsubscribe at any time. We value your privacy. Our mailing list is private and will never be sold or shared with a third party. Review our Privacy Policy here.
References
(2019). Lambert-Eaton Myasthenic Syndrome. National Organization for Rare Disorders (NORD). https://rarediseases.org/rare-diseases/lambert-eaton-myasthenic-syndrome/
(2023). Jayarangaiah A, Theetha Kariyanna P. Lambert-Eaton Myasthenic Syndrome. National Library of Medicine (NIH). https://www.ncbi.nlm.nih.gov/books/NBK507891/
